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Title: Multidrug resistance proteins: role of P-glycoprotein, MRP1, MRP2, and BCRP (ABCG2) in tissue defense

Journal Article · · Toxicology and Applied Pharmacology
 [1];  [2];  [2]
  1. Division of Drug Delivery and Disposition, School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599 (United States)
  2. Cancer Research Laboratories, Queen's University, 3rd Floor, Botterell Hall, Kingston, Ontario, K7L 3N6 (Canada)

In tumor cell lines, multidrug resistance is often associated with an ATP-dependent decrease in cellular drug accumulation which is attributed to the overexpression of certain ATP-binding cassette (ABC) transporter proteins. ABC proteins that confer drug resistance include (but are not limited to) P-glycoprotein (gene symbol ABCB1), the multidrug resistance protein 1 (MRP1, gene symbol ABCC1), MRP2 (gene symbol ABCC2), and the breast cancer resistance protein (BCRP, gene symbol ABCG2). In addition to their role in drug resistance, there is substantial evidence that these efflux pumps have overlapping functions in tissue defense. Collectively, these proteins are capable of transporting a vast and chemically diverse array of toxicants including bulky lipophilic cationic, anionic, and neutrally charged drugs and toxins as well as conjugated organic anions that encompass dietary and environmental carcinogens, pesticides, metals, metalloids, and lipid peroxidation products. P-glycoprotein, MRP1, MRP2, and BCRP/ABCG2 are expressed in tissues important for absorption (e.g., lung and gut) and metabolism and elimination (liver and kidney). In addition, these transporters have an important role in maintaining the barrier function of sanctuary site tissues (e.g., blood-brain barrier, blood-cerebral spinal fluid barrier, blood-testis barrier and the maternal-fetal barrier or placenta). Thus, these ABC transporters are increasingly recognized for their ability to modulate the absorption, distribution, metabolism, excretion, and toxicity of xenobiotics. In this review, the role of these four ABC transporter proteins in protecting tissues from a variety of toxicants is discussed. Species variations in substrate specificity and tissue distribution of these transporters are also addressed since these properties have implications for in vivo models of toxicity used for drug discovery and development.

OSTI ID:
20721791
Journal Information:
Toxicology and Applied Pharmacology, Vol. 204, Issue 3; Other Information: DOI: 10.1016/j.taap.2004.10.012; PII: S0041-008X(04)00482-X; Copyright (c) 2004 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0041-008X
Country of Publication:
United States
Language:
English